Don't let the computer decide for you
@markku.niskanen :
I am sorry to say so, but if you run a newly installed program without verifying (customizing) the default settings, you are asking for trouble. In these cases, not the program, but the user is to blamE; CCleaner never gave me any problem on XP SP3. I never blindly allow a program to run with default settings.
Registry cleaners ? I'm glad they're around.